tetano
Editor, Senior Moderator
Published Date: 2013-07-01 01:13:54
Subject: PRO/AH/EDR> Equine influenza, equine - UK
Archive Number: 20130701.1800416
EQUINE INFLUENZA, EQUINE - UK
*****************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org
Date: 28 Jun 2013
Source: Animal Health Trust [edited]
http://www.aht.org.uk/icc/Interim_Report12_June13.html
On 28 Jun 2013, the Animal Health Trust confirmed an outbreak of equine influenza in Hertfordshire. The affected horse was a one-month-old cob filly that showed clinical signs of depression, pyrexia and pneumonia. A positive diagnosis was made by qPCR on a nasopharyngeal swab. The filly's dam, a 3-year-old cob assumed to be non-vaccinated, showed clinical signs of pyrexia and a cough. Six other horses have shown similar clinical signs at the premises in Essex from which the mare and foal originated.
--
Communicated by:
Julie Magnus MA. Ed. Adv. Dip. Ed.
<Jmrtnewmarket@aol.com>
[Equine influenza is highly contagious and spreads rapidly among susceptible horses. Two immunologically distinct influenza viruses have been found in horse populations worldwide except in Australia and New Zealand. Orthomyxovirus (influenza) A/Equi-1 has not been isolated since 1980. Orthomyxovirus (influenza) A/Equi-2 was 1st recognized in 1963 as a cause of widespread epidemics and has subsequently become endemic in many countries.
Endemicity is maintained by sporadic clinical cases and by inapparent infection in susceptible horses that are introduced into the population by birth, through waning immunity, or after movement from other areas or countries. A carrier state is not recognized for equine influenza. The clinical outcome after viral exposure largely depends on immune status; clinical disease varies from a mild, inapparent infection to severe disease in susceptible animals. Influenza is rarely fatal except in donkeys, zebras, and debilitated horses. Transmission occurs by inhalation of respiratory secretions. Epidemics arise when one or more acutely infected horses are introduced into a susceptible group. The epidemiologic outcome depends on the antigenic characteristics of the circulating virus and the immune status of a given population of horses at time of exposure. Frequent natural exposure or regular vaccination may contribute to the degree of antigenic drift observed with specific strains of A/Equi-2 virus in some parts of the world.
The incubation period of influenza is about 1-3 days. Clinical signs begin abruptly and include high fever (up to 106 F [41.1 C]), serous nasal discharge, submandibular lymphadenopathy, and coughing that is dry, harsh, and nonproductive. Depression, anorexia, and weakness are frequently observed. Clinical signs usually last slightly less than 3 days in uncomplicated cases. Influenza virus replicates within respiratory epithelial cells, resulting in destruction of tracheal and bronchial epithelium and cilia. Young horses seem to be the most susceptible. All ages of horses with mild infection may take 2-3 weeks to recover. Those that are severely affected may take 6 months to recover. Along the road to recovery, these horses are subject to bacterial infection, especially pneumonia and bronchitis.
The presence of a rapidly spread respiratory infection in a group of horses characterized by rapid onset, high fever, depression, and cough is presumptive evidence of equine influenza. Definitive diagnosis can be determined by virus isolation, influenza A antigen detection, or paired serology (hemagglutination inhibition). Nasopharyngeal swabs are obtained for virus isolation and antigen detection. Samples need to be taken as early as the clinical signs are recognized.
Antibiotics are recommended if the fever persists longer than 3 days or if purulent nasal discharge is present. Horses should be rested one week for every day of fever with a minimum of 3 week rest (to allow regeneration of the mucociliary apparatus). NSAID (non-steroidal anti-inflammatory drugs) are recommended for horses with a fever of 104 F (40 C) or higher.
Prevention of influenza requires hygienic management practices and vaccination. Exposure can be reduced by isolation of newly introduced horses for 2 weeks. Numerous vaccines are commercially available for prevention of equine influenza. An intranasal modified live influenza vaccine, designed to induce mucosal (local) antibody protection, has demonstrated protection against natural challenge. This vaccine is temperature sensitive and is not capable of replicating beyond the nasal passages. The majority of commercially available influenza vaccines are inactivated, adjuvanted vaccines recommended primarily for IM administration. Because the duration of protection provided by current vaccines is limited, booster injections probably should be administered often, e.g., every 3-6 months. Vaccine manufacturers monitor continuously to ensure that influenza strain content reflects as closely as possible the antigenicity of current strains of field virus.
Equine influenza viruses are influenza viruses adapted to propagation in horses and other equines and are not transmissible to other animals, except occasionally to dogs. They are usually antigenically H7N7 or H3N8. There are vaccines available for both types.
Portions of this comment have been extracted from: http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121303.htm. - Mod.TG
A HealthMap/ProMED-mail map can be accessed at: http://healthmap.org/r/1lNY.]
http://beta.promedmail.org/direct.php?id=20130701.1800416
Subject: PRO/AH/EDR> Equine influenza, equine - UK
Archive Number: 20130701.1800416
EQUINE INFLUENZA, EQUINE - UK
*****************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org
Date: 28 Jun 2013
Source: Animal Health Trust [edited]
http://www.aht.org.uk/icc/Interim_Report12_June13.html
On 28 Jun 2013, the Animal Health Trust confirmed an outbreak of equine influenza in Hertfordshire. The affected horse was a one-month-old cob filly that showed clinical signs of depression, pyrexia and pneumonia. A positive diagnosis was made by qPCR on a nasopharyngeal swab. The filly's dam, a 3-year-old cob assumed to be non-vaccinated, showed clinical signs of pyrexia and a cough. Six other horses have shown similar clinical signs at the premises in Essex from which the mare and foal originated.
--
Communicated by:
Julie Magnus MA. Ed. Adv. Dip. Ed.
<Jmrtnewmarket@aol.com>
[Equine influenza is highly contagious and spreads rapidly among susceptible horses. Two immunologically distinct influenza viruses have been found in horse populations worldwide except in Australia and New Zealand. Orthomyxovirus (influenza) A/Equi-1 has not been isolated since 1980. Orthomyxovirus (influenza) A/Equi-2 was 1st recognized in 1963 as a cause of widespread epidemics and has subsequently become endemic in many countries.
Endemicity is maintained by sporadic clinical cases and by inapparent infection in susceptible horses that are introduced into the population by birth, through waning immunity, or after movement from other areas or countries. A carrier state is not recognized for equine influenza. The clinical outcome after viral exposure largely depends on immune status; clinical disease varies from a mild, inapparent infection to severe disease in susceptible animals. Influenza is rarely fatal except in donkeys, zebras, and debilitated horses. Transmission occurs by inhalation of respiratory secretions. Epidemics arise when one or more acutely infected horses are introduced into a susceptible group. The epidemiologic outcome depends on the antigenic characteristics of the circulating virus and the immune status of a given population of horses at time of exposure. Frequent natural exposure or regular vaccination may contribute to the degree of antigenic drift observed with specific strains of A/Equi-2 virus in some parts of the world.
The incubation period of influenza is about 1-3 days. Clinical signs begin abruptly and include high fever (up to 106 F [41.1 C]), serous nasal discharge, submandibular lymphadenopathy, and coughing that is dry, harsh, and nonproductive. Depression, anorexia, and weakness are frequently observed. Clinical signs usually last slightly less than 3 days in uncomplicated cases. Influenza virus replicates within respiratory epithelial cells, resulting in destruction of tracheal and bronchial epithelium and cilia. Young horses seem to be the most susceptible. All ages of horses with mild infection may take 2-3 weeks to recover. Those that are severely affected may take 6 months to recover. Along the road to recovery, these horses are subject to bacterial infection, especially pneumonia and bronchitis.
The presence of a rapidly spread respiratory infection in a group of horses characterized by rapid onset, high fever, depression, and cough is presumptive evidence of equine influenza. Definitive diagnosis can be determined by virus isolation, influenza A antigen detection, or paired serology (hemagglutination inhibition). Nasopharyngeal swabs are obtained for virus isolation and antigen detection. Samples need to be taken as early as the clinical signs are recognized.
Antibiotics are recommended if the fever persists longer than 3 days or if purulent nasal discharge is present. Horses should be rested one week for every day of fever with a minimum of 3 week rest (to allow regeneration of the mucociliary apparatus). NSAID (non-steroidal anti-inflammatory drugs) are recommended for horses with a fever of 104 F (40 C) or higher.
Prevention of influenza requires hygienic management practices and vaccination. Exposure can be reduced by isolation of newly introduced horses for 2 weeks. Numerous vaccines are commercially available for prevention of equine influenza. An intranasal modified live influenza vaccine, designed to induce mucosal (local) antibody protection, has demonstrated protection against natural challenge. This vaccine is temperature sensitive and is not capable of replicating beyond the nasal passages. The majority of commercially available influenza vaccines are inactivated, adjuvanted vaccines recommended primarily for IM administration. Because the duration of protection provided by current vaccines is limited, booster injections probably should be administered often, e.g., every 3-6 months. Vaccine manufacturers monitor continuously to ensure that influenza strain content reflects as closely as possible the antigenicity of current strains of field virus.
Equine influenza viruses are influenza viruses adapted to propagation in horses and other equines and are not transmissible to other animals, except occasionally to dogs. They are usually antigenically H7N7 or H3N8. There are vaccines available for both types.
Portions of this comment have been extracted from: http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121303.htm. - Mod.TG
A HealthMap/ProMED-mail map can be accessed at: http://healthmap.org/r/1lNY.]
http://beta.promedmail.org/direct.php?id=20130701.1800416